I am very new to telescopes and have access to a wonderful telescope through my astronomy club. Our club is relatively new and thus there is no one with a lot of experience with our mount/telescope to guide us and teach us.
We have a Celestron Edge HD 11" telescope that goes on this mount and we have noticed an issue we are having that I am trying to figure out is normal or if there is something off, such as orthogonality.
The telescope and mount are not permanent, and are always broken down and put up every time that we use it. We set it up and polar align it with RAPAS. After that we slew to a bright star and RE-CAL on it. Now if it stays on one side of the meridian, it is fine. It will have no problem locating objects and centering on them. However when it does a meridian flip, it will then be off by about .5 degrees. Without doing another RE-CAL on that side, if we slew back then it centers again no problem. This seems odd to me. How can it be fine on one side, off on the other, and then go back to the same side and be fine again? Doesn't matter if you slew east and RE-CAL or if you start with the west and RE-CAL. As soon as it crosses the meridian it is off by .5 degrees.
Is it normal for the scope to be fine on one side, say the west, and then when slewing to the east and crossing the meridian to be off by a little bit? I don't believe that we have tested it by slewing to the west and doing RE-CAL and then slewing east and doing RE-CAL and then going back west then east again to see if it still centers on both sides. Or we might have but I cannot remember. I also am not sure I am fully understanding what RE-CAL is. When it re-calibrates, does it re-calibrate on one object and then if you re-calibrate on another it forgets that object? Or if you re-calibrate on more than one object, it remembers all of them and provides a more accurate calibration?
We only use a keypad to control the mount right now. So any help for using the keypad only would be awesome!
And any help would be greatly appreciated before we start trying to address possible orthogonality issues. Thank you in advance!!!
Edited by extremeastrobabe, 25 August 2019 - 01:42 AM.